Why do we need ventilation shafts in mines?

Question

i'm not really interested in mines by the way

this is for my science home work

i can't find anythingg on google

and i think my teacher might eat me if i don't do it so please help.....

?

ox.

Answer 1

WE GO THROUGH LESS MINERS THAT WAY.

Answer 2

It can serve two purposes.  One, venting gases and two, supplying fresh air for the miners.

Answer 3

well.......shafts to take the dirty air out, and shafts to pull the clean air in....simple enough? Not trying to be cute, that's just the reason!  Coal dust /methane is highly combustable. That's why in the old days they used to take canary birds down in the mines(because they were the best litmus test for being overcome by methane gas)if the bird croaked in other words--"get outta here!"....Now,due to all the recent mine disasters,they're considering making excape shafts to the surface as well..and they've developed a much better survival suit in case you're trapped in the mine..'bout time,huh?.....it's still a dirty job, but pays really good and for many people it's all they've ever done,or have a chance to do..sorta' inherited. You know the risks going in so nothings a surprise..you just put it in the back of your mind and think of how it keeps your family going.

Answer 4

Usual way of aspirating a mine is with a huge extractor fan which sucks out 'stale air' from a secondary shaft, allowing clean air to enter the mine by the main shaft (or drift).

This ventilation considerably reduces the chances of a build up of dangerous gases the main ones being :-

Methane (CH4), known as 'fire damp' (highly flammable)

Carbon Dioxide (CO2) and Nitrogen (N), known as 'black damp'.

Carbon Monoxide (CO), known as 'white damp'

There are others, which I am sure you could find with a more thorough search.

Just as a matter of interest, every miner at one time, (don't know about now) carried what was known as a 'Self Rescuer'. This was a mask which converted CO into CO2, and gave about an hour of fairly safe air to allow time to get to the surface or at least to a clean area.

How's that then? Not comprehensive, but at least it will give you a start.

Hope it helps.